The present invention relates generally to high resolution graphic production, and more specifically, relates to real time data processing of multiple image data to produce a composite.
In reproduction technology, it is often desirable to combine multiple texts, photographic images, and geometric shapes into a single proof based upon layout information generated by some form of digital input. This input may be generated by a digital scanner or electronic work station which is used to create a montage. The layout information may have a variety of formats and protocols.
The majority of color separation films produced in the graphic arts industry currently are made using drum output recorders. Three data types (i.e., contone, contour, and run-length) are commonly used for storing and manipulating images that are converted to halftone pixels for output to these recorders.
The conversion process is typically preceded by a lengthy pre-processing step called a final page run, in which the three data types are converted into a common data format and the multiple images of the same data type are merged into one single file. Even though the resulting data stream defines a high-quality, high-resolution, four color separated image, the final page run unfortunately takes about an hour to complete. The commercially available Hell Chromacom 1000 system coupled to a DC 350 output recorder operates in this fashion.
Higher speed can be achieved in lower quality systems. These typically employ flatbed rather than drum recorders. Such systems tend to have fewer levels of grey in the halftone pixels, lesser precision in the output process, and greater susceptibility to moire patterns. Typical, commercially available systems of this type include the Hell LS-210 system and the Scitex Raystar system. Even though these systems sacrifice quality of output for enhanced speed, real time operation is seldom achieved because the output recorder must frequently pause in mid-image to permit the hardware to convert multiple image data types into halftone pixels.
U.S. Pat. No. 4,729,037, Doelves, is concerned with the production of printed material using image input from multiple sources. The system is designed for production of catalogs using high resolution data to be received from a scanner and relatively lower resolution data from a digital memory. To function in near real time, the system requires the data to be presented from the data sources synchronously.
A more flexible system is disclosed in U.S. Pat. No. 4,849,822, Sing. In this system, data may be added to an image from a digital work station. This permits text to be placed over high resolution images. To permit mixing of these images, however, the lower resolution inputs must be expanded and synchronously intermixed with the higher resolution input. Thus, the various components of the final proof cannot be stored in memory without an inordinate amount of hardware. The result is that the work station operator is limited in his ability to manipulate the data.
The Sing system is further limited in the types of data which can be processed automatically without operator supervision. High resolution compressed data, for example, must be expanded under direct operator control before it can be intermixed with other data types. High resolution contour data involving a color change within a pixel must be similarly processed by the operator before being combined.
U.S. Pat. No. 4,419,690, Hammes, shows a system which has a limited capacity to process input data of varying resolutions. A more flexible system is shown in U.S. Pat. No. 4,647,962, Rosen, et al. Though the system of Rosen, et al. provides for a greater range in the resolution of the input data, combining multiple images in the same proof is not provided without direct operator supervision.
Thus, these systems have limited capability to combine multiple images of varying resolution in real time to produce a composite.